1. She said that we must go there.
2. She says that we must go there.
And also take a look on my punctuation marks. Thanks
Either, in the appropriate context, but without the commas.
1 is ambiguous. There is an old(ish) use of "must" as a simple past; in this case, it would be more common to say 'She said that we had to/were obliged to go there,' though some native speakers (usually the ones with less hair ) would still use 'must'. The other meaning of 1 is that she said (at some time in the past) that (at any possible opportunity in the future) we should go: 'If you ever go to London, you must visit the Museum of Childhood at Bethnal Green'.
1 - simple past: you must = you had to (this usage is dying out; best ignored for ESOL purposes )
2 - present statement about future advisability (not obligation)
(these are the two meanings I discussed in my last post; there's another -
2a - present command about [near-]future obligation )